Electrochemical Zone

Challengeand SolutionSpills of chlorinated solvents are a main concern of the Capital Region of Denmark, since they threaten the groundwater resources we use for drinking water.

Once the chlorinated solvents reach the groundwater aquifers, they are difficult to treat effectively. Pump-and-treat systems are commonly used, but these are long-term solutions with substantial operation and maintenance costs. So the Capital Region is involved in development of methods that can treat the groundwater in the aquifers without the need to pump water to the surface.

One possible solution is to clean contaminated groundwater using electricity, since electric current can create reactants that degrade the contamination to harmless substances in the aquifer. In an industrial PhD-project, a groundwater aquifer is simulated to test if electrochemical remediation is a solution to our challenges. If successful, we will try out the method in the ground.

Brief Technical DetailsAn electrochemical zone for in situ degradation of chlorinated solvents may be a viable alternative to pump-and-treat. Near the electrodes we can obtain fast electrochemical reduction of chlorinated solvents and we may also be able to generate reactants, which bacteria can subsequently use in biodegradation processes.

The focus is on intelligent use and combination of the different electrochemical processes to optimize the zone for chemical and biological degradation of the chlorinated solvents. Experimental work in a 1D soil column and a 2D sand box will be conducted on both sand and limestone to reflect natural Danish groundwater reservoir geologies before advancing the technology to in situ testing.